The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
Wikipedia's[3] MV Paul R. Tregurtha article gives 10 May 1981 as the ship's maiden voyage, following its 4 February 1981 launch as the William J. DeLancey.
Operator's own fleet page describing the ship's history and specifications.[1]
Gives the launch (4 Feb 1981), christening and 10 May 1981 maiden voyage dates, plus the 1990 renaming.[1]
Something missing or wrong? Say it in your own words: a link that backs this pin up, a different start or end date and why, or a fact it lacks or gets wrong. The AI checks it against this pin's sources, searches for better ones, and adds any page that backs you up. The pin's own sources still count most.